In prior art methods for the chemical treatment and compaction of inorganic waste materials high quantities of water are added and high quantities of binder are required. In such methods the reaction mixture usually has the consistency of a pumpable mixture. Due to the use of the high quantities of additives these methods have the disadvantage of a large increase in the volume of waste.
One prior art method for the physical treatment and compaction of inorganic waste materials comprises compacting the waste under pressure. The inorganic waste materials are mixed with each other in accordance with appropriate specifications and compressed at high pressures to form solid compacts. Due to the low permeability of the slabs their elutability is reduced. These waste slabs are transported to the disposal site and placed in the disposal unit in modular form. Although this method has the advantage over the abovementioned methods of saving space in the disposal unit the compacts are not dimensionally stable under water and their constituents can be reeluted after prolonged exposure to water.
The prior art is further described in the following literature references